Fame and reputations

A man wins and then he is well mentioned,
Until he is ascribed things he didn’t even do.
And you will see the scoundrel whose defects are well known,
Is sad and held accountable for things he didn’t even do.

The poem is stressing the importance of reputations and how they affect the verdicts of people so much so that they will draw the opposite conclusion to a situation just because the person in question has a reputation for that response.
So for example if an Imam who is known for his piety is seen picking up something from a shop counter without paying for it then the first reaction of people will likely be to assume that he has already paid for it or that he was given it free on a prior arrangement. Of course this may not be true, but that is the power of the reputation.
On the other hand you have a known thief who also picks up something without paying for it. The first reaction of the onlookers will be that he is stealing that, though this may not be the case again.
But of course reputations are built over time and through substance. One cannot create a reputation from thin air. Good reputations only come through time and consistent good dealings and conduct.